You should give it a go. Ok, maybe you don't get hard sunlight all the time, but then again, Cascade is very tolerant and even if the output isn't as much as most over here would get, it would still likely be not too bad. I'd shop around nearby and see if anyone over there would sell you a rhizome or two.

I think you could grow them. The biggest problem would be disease. If you could plant them in a fairly open area and put some extra space between them you might have some success. The key is good air circulation. You'd also want to keep any extra sprouts pruned off at ground level. Once you've selected the several you want, prune of any other suckers that come up. Air circulation is poorest near the ground so you want to keep that as clear as possible. You might even want to plant them at the top of little mounds (1-2 ft tall or so). This would also help keep their toes moist, but not wet.

Actually, the further North you are, the better, as long as it isn't too cold. Longer days promote more growth and flowering. They grow fine in places where the average night temp can be -5 C for a couple months.